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 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package javax.xml.bind;

import javax.xml.bind.annotation.adapters.XmlAdapter;
import javax.xml.bind.attachment.AttachmentUnmarshaller;
import javax.xml.validation.Schema;
import java.io.Reader;

/**
 * The <tt>Unmarshaller</tt> class governs the process of deserializing XML data into newly created
 * Java content trees, optionally validating the XML data as it is unmarshalled.  It provides an
 * overloading of unmarshal methods for many different input kinds.
 *
 * <p> Unmarshalling from a File: <blockquote>
 * <pre>
 *       JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 *       Unmarshaller u = jc.createUnmarshaller();
 *       Object o = u.unmarshal( new File( "nosferatu.xml" ) );
 *    </pre>
 * </blockquote>
 *
 *
 * <p> Unmarshalling from an InputStream: <blockquote>
 * <pre>
 *       InputStream is = new FileInputStream( "nosferatu.xml" );
 *       JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 *       Unmarshaller u = jc.createUnmarshaller();
 *       Object o = u.unmarshal( is );
 *    </pre>
 * </blockquote>
 *
 * <p> Unmarshalling from a URL: <blockquote>
 * <pre>
 *       JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 *       Unmarshaller u = jc.createUnmarshaller();
 *       URL url = new URL( "http://beaker.east/nosferatu.xml" );
 *       Object o = u.unmarshal( url );
 *    </pre>
 * </blockquote>
 *
 * <p> Unmarshalling from a StringBuffer using a <tt>javax.xml.transform.stream.StreamSource</tt>:
 * <blockquote>
 * <pre>
 *       JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 *       Unmarshaller u = jc.createUnmarshaller();
 *       StringBuffer xmlStr = new StringBuffer( "&lt;?xml version=&quot;1.0&quot;?&gt;..." );
 *       Object o = u.unmarshal( new StreamSource( new StringReader( xmlStr.toString() ) ) );
 *    </pre>
 * </blockquote>
 *
 * <p> Unmarshalling from a <tt>org.w3c.dom.Node</tt>: <blockquote>
 * <pre>
 *       JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 *       Unmarshaller u = jc.createUnmarshaller();
 *
 *       DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
 *       dbf.setNamespaceAware(true);
 *       DocumentBuilder db = dbf.newDocumentBuilder();
 *       Document doc = db.parse(new File( "nosferatu.xml"));
 *
 *       Object o = u.unmarshal( doc );
 *    </pre>
 * </blockquote>
 *
 * <p> Unmarshalling from a <tt>javax.xml.transform.sax.SAXSource</tt> using a client specified
 * validating SAX2.0 parser: <blockquote>
 * <pre>
 *       // configure a validating SAX2.0 parser (Xerces2)
 *       static final String JAXP_SCHEMA_LANGUAGE =
 *           "http://java.sun.com/xml/jaxp/properties/schemaLanguage";
 *       static final String JAXP_SCHEMA_LOCATION =
 *           "http://java.sun.com/xml/jaxp/properties/schemaSource";
 *       static final String W3C_XML_SCHEMA =
 *           "http://www.w3.org/2001/XMLSchema";
 *
 *       System.setProperty( "javax.xml.parsers.SAXParserFactory",
 *                           "org.apache.xerces.jaxp.SAXParserFactoryImpl" );
 *
 *       SAXParserFactory spf = SAXParserFactory.newInstance();
 *       spf.setNamespaceAware(true);
 *       spf.setValidating(true);
 *       SAXParser saxParser = spf.newSAXParser();
 *
 *       try {
 *           saxParser.setProperty(JAXP_SCHEMA_LANGUAGE, W3C_XML_SCHEMA);
 *           saxParser.setProperty(JAXP_SCHEMA_LOCATION, "http://....");
 *       } catch (SAXNotRecognizedException x) {
 *           // exception handling omitted
 *       }
 *
 *       XMLReader xmlReader = saxParser.getXMLReader();
 *       SAXSource source =
 *           new SAXSource( xmlReader, new InputSource( "http://..." ) );
 *
 *       // Setup JAXB to unmarshal
 *       JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 *       Unmarshaller u = jc.createUnmarshaller();
 *       ValidationEventCollector vec = new ValidationEventCollector();
 *       u.setEventHandler( vec );
 *
 *       // turn off the JAXB provider's default validation mechanism to
 *       // avoid duplicate validation
 *       u.setValidating( false )
 *
 *       // unmarshal
 *       Object o = u.unmarshal( source );
 *
 *       // check for events
 *       if( vec.hasEvents() ) {
 *          // iterate over events
 *       }
 *    </pre>
 * </blockquote>
 *
 * <p> Unmarshalling from a StAX XMLStreamReader: <blockquote>
 * <pre>
 *       JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 *       Unmarshaller u = jc.createUnmarshaller();
 *
 *       javax.xml.stream.XMLStreamReader xmlStreamReader =
 *           javax.xml.stream.XMLInputFactory().newInstance().createXMLStreamReader( ... );
 *
 *       Object o = u.unmarshal( xmlStreamReader );
 *    </pre>
 * </blockquote>
 *
 * <p> Unmarshalling from a StAX XMLEventReader: <blockquote>
 * <pre>
 *       JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 *       Unmarshaller u = jc.createUnmarshaller();
 *
 *       javax.xml.stream.XMLEventReader xmlEventReader =
 *           javax.xml.stream.XMLInputFactory().newInstance().createXMLEventReader( ... );
 *
 *       Object o = u.unmarshal( xmlEventReader );
 *    </pre>
 * </blockquote>
 *
 * <p> <a name="unmarshalEx"></a> <b>Unmarshalling XML Data</b><br> <blockquote> Unmarshalling can
 * deserialize XML data that represents either an entire XML document or a subtree of an XML
 * document. Typically, it is sufficient to use the unmarshalling methods described by <a
 * href="#unmarshalGlobal">Unmarshal root element that is declared globally</a>. These unmarshal
 * methods utilize {@link JAXBContext}'s mapping of global XML element declarations and type
 * definitions to JAXB mapped classes to initiate the unmarshalling of the root element of  XML
 * data.  When the {@link JAXBContext}'s mappings are not sufficient to unmarshal the root element
 * of XML data, the application can assist the unmarshalling process by using the <a
 * href="#unmarshalByDeclaredType">unmarshal by declaredType methods</a>. These methods are useful
 * for unmarshalling XML data where the root element corresponds to a local element declaration in
 * the schema. </blockquote>
 *
 * <blockquote> An unmarshal method never returns null. If the unmarshal process is unable to
 * unmarshal the root of XML content to a JAXB mapped object, a fatal error is reported that
 * terminates processing by throwing JAXBException. </blockquote>
 *
 * <p> <a name="unmarshalGlobal"></a> <b>Unmarshal a root element that is globally declared</b><br>
 * <blockquote> The unmarshal methods that do not have an <tt>declaredType</tt> parameter use {@link
 * JAXBContext} to unmarshal the root element of an XML data. The {@link JAXBContext} instance is
 * the one that was used to create this <tt>Unmarshaller</tt>. The {@link JAXBContext} instance
 * maintains a mapping of globally declared XML element and type definition names to JAXB mapped
 * classes. The unmarshal method checks if {@link JAXBContext} has a mapping from the root element's
 * XML name and/or <tt>@xsi:type</tt> to a JAXB mapped class.  If it does, it umarshalls the XML
 * data using the appropriate JAXB mapped class. Note that when the root element name is unknown and
 * the root element has an <tt>@xsi:type</tt>, the XML data is unmarshalled using that JAXB mapped
 * class as the value of a {@link JAXBElement}. When the {@link JAXBContext} object does not have a
 * mapping for the root element's name nor its <tt>@xsi:type</tt>, if it exists, then the unmarshal
 * operation will abort immediately by throwing a {@link UnmarshalException UnmarshalException}.
 * This exception scenario can be worked around by using the unmarshal by declaredType methods
 * described in the next subsection. </blockquote>
 *
 * <p> <a name="unmarshalByDeclaredType"></a> <b>Unmarshal by Declared Type</b><br> <blockquote> The
 * unmarshal methods with a <code>declaredType</code> parameter enable an application to deserialize
 * a root element of XML data, even when there is no mapping in {@link JAXBContext} of the root
 * element's XML name. The unmarshaller unmarshals the root element using the application provided
 * mapping specified as the <tt>declaredType</tt> parameter. Note that even when the root element's
 * element name is mapped by {@link JAXBContext}, the <code>declaredType</code> parameter overrides
 * that mapping for deserializing the root element when using these unmarshal methods. Additionally,
 * when the root element of XML data has an <tt>xsi:type</tt> attribute and that attribute's value
 * references a type definition that is mapped to a JAXB mapped class by {@link JAXBContext}, that
 * the root element's <tt>xsi:type</tt> attribute takes precedence over the unmarshal methods
 * <tt>declaredType</tt> parameter. These methods always return a <tt>JAXBElement&lt;declaredType></tt>
 * instance. The table below shows how the properties of the returned JAXBElement instance are set.
 *
 * <a name="unmarshalDeclaredTypeReturn"></a> <p> <table border="2" rules="all" cellpadding="4">
 * <thead> <tr> <th align="center" colspan="2"> Unmarshal By Declared Type returned JAXBElement
 * </tr> <tr> <th>JAXBElement Property</th> <th>Value</th> </tr> <tr> <td>name</td> <td><code>xml
 * element name</code></td> </tr> </thead> <tbody> <tr> <td>value</td> <td><code>instanceof
 * declaredType</code></td> </tr> <tr> <td>declaredType</td> <td>unmarshal method
 * <code>declaredType</code> parameter</td> </tr> <tr> <td>scope</td> <td><code>null</code>
 * <i>(actual scope is unknown)</i></td> </tr> </tbody> </table> </blockquote>
 *
 * <p> The following is an example of <a href="#unmarshalByDeclaredType">unmarshal by declaredType
 * method</a>. <p> Unmarshal by declaredType from a <tt>org.w3c.dom.Node</tt>: <blockquote>
 * <pre>
 *       Schema fragment for example
 *       &lt;xs:schema>
 *          &lt;xs:complexType name="FooType">...&lt;\xs:complexType>
 *          &lt;!-- global element declaration "PurchaseOrder" -->
 *          &lt;xs:element name="PurchaseOrder">
 *              &lt;xs:complexType>
 *                 &lt;xs:sequence>
 *                    &lt;!-- local element declaration "foo" -->
 *                    &lt;xs:element name="foo" type="FooType"/>
 *                    ...
 *                 &lt;/xs:sequence>
 *              &lt;/xs:complexType>
 *          &lt;/xs:element>
 *       &lt;/xs:schema>
 *
 *       JAXBContext jc = JAXBContext.newInstance( "com.acme.foo" );
 *       Unmarshaller u = jc.createUnmarshaller();
 *
 *       DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
 *       dbf.setNamespaceAware(true);
 *       DocumentBuilder db = dbf.newDocumentBuilder();
 *       Document doc = db.parse(new File( "nosferatu.xml"));
 *       Element  fooSubtree = ...; // traverse DOM till reach xml element foo, constrained by a
 *                                  // local element declaration in schema.
 *
 *       // FooType is the JAXB mapping of the type of local element declaration foo.
 *       JAXBElement&lt;FooType> foo = u.unmarshal( fooSubtree, FooType.class);
 *    </pre>
 * </blockquote>
 *
 * <p> <b>Support for SAX2.0 Compliant Parsers</b><br> <blockquote> A client application has the
 * ability to select the SAX2.0 compliant parser of their choice.  If a SAX parser is not selected,
 * then the JAXB Provider's default parser will be used.  Even though the JAXB Provider's default
 * parser is not required to be SAX2.0 compliant, all providers are required to allow a client
 * application to specify their own SAX2.0 parser.  Some providers may require the client
 * application to specify the SAX2.0 parser at schema compile time. See {@link
 * #unmarshal(javax.xml.transform.Source) unmarshal(Source)} for more detail. </blockquote>
 *
 * <p> <b>Validation and Well-Formedness</b><br> <blockquote> <p> A client application can enable or
 * disable JAXP 1.3 validation mechanism via the <tt>setSchema(javax.xml.validation.Schema)</tt>
 * API. Sophisticated clients can specify their own validating SAX 2.0 compliant parser and bypass
 * the JAXP 1.3 validation mechanism using the {@link #unmarshal(javax.xml.transform.Source)
 * unmarshal(Source)}  API.
 *
 * <p> Since unmarshalling invalid XML content is defined in JAXB 2.0, the Unmarshaller default
 * validation event handler was made more lenient than in JAXB 1.0.  When schema-derived code
 * generated by JAXB 1.0 binding compiler is registered with {@link JAXBContext}, the default
 * unmarshal validation handler is {@link javax.xml.bind.helpers.DefaultValidationEventHandler} and
 * it terminates the marshal  operation after encountering either a fatal error or an error. For a
 * JAXB 2.0 client application, there is no explicitly defined default validation handler and the
 * default event handling only terminates the unmarshal operation after encountering a fatal error.
 *
 * </blockquote>
 *
 * <p> <a name="supportedProps"></a> <b>Supported Properties</b><br> <blockquote> <p> There
 * currently are not any properties required to be supported by all JAXB Providers on Unmarshaller.
 * However, some providers may support their own set of provider specific properties. </blockquote>
 *
 * <p> <a name="unmarshalEventCallback"></a> <b>Unmarshal Event Callbacks</b><br> <blockquote> The
 * {@link Unmarshaller} provides two styles of callback mechanisms that allow application specific
 * processing during key points in the unmarshalling process.  In 'class defined' event callbacks,
 * application specific code placed in JAXB mapped classes is triggered during unmarshalling.
 * 'External listeners' allow for centralized processing of unmarshal events in one callback method
 * rather than by type event callbacks. <p> 'Class defined' event callback methods allow any JAXB
 * mapped class to specify its own specific callback methods by defining methods with the following
 * method signature: <blockquote>
 * <pre>
 *   // This method is called immediately after the object is created and before the unmarshalling
 * of this
 *   // object begins. The callback provides an opportunity to initialize JavaBean properties prior
 * to unmarshalling.
 *   void beforeUnmarshal(Unmarshaller, Object parent);
 *
 *   //This method is called after all the properties (except IDREF) are unmarshalled for this
 * object,
 *   //but before this object is set to the parent object.
 *   void afterUnmarshal(Unmarshaller, Object parent);
 * </pre>
 * </blockquote> The class defined callback methods should be used when the callback method requires
 * access to non-public methods and/or fields of the class. <p> The external listener callback
 * mechanism enables the registration of a {@link Listener} instance with an {@link
 * Unmarshaller#setListener(Listener)}. The external listener receives all callback events, allowing
 * for more centralized processing than per class defined callback methods.  The external listener
 * receives events when unmarshalling proces is marshalling to a JAXB element or to JAXB mapped
 * class. <p> The 'class defined' and external listener event callback methods are independent of
 * each other, both can be called for one event.  The invocation ordering when both listener
 * callback methods exist is defined in {@link Listener#beforeUnmarshal(Object, Object)} and {@link
 * Listener#afterUnmarshal(Object, Object)}. <p> An event callback method throwing an exception
 * terminates the current unmarshal process.
 *
 * </blockquote>
 *
 * @author <ul><li>Ryan Shoemaker, Sun Microsystems, Inc.</li><li>Kohsuke Kawaguchi, Sun
 *         Microsystems, Inc.</li><li>Joe Fialli, Sun Microsystems, Inc.</li></ul>
 * @see JAXBContext
 * @see Marshaller
 * @see Validator
 * @since JAXB1.0
 */
public interface Unmarshaller {

  /**
   * Unmarshal XML data from the specified file and return the resulting
   * content tree.
   *
   * <p>
   * Implements <a href="#unmarshalGlobal">Unmarshal Global Root Element</a>.
   *
   * @param f the file to unmarshal XML data from
   * @return the newly created root object of the java content tree
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If the file parameter is null
   */
  public Object unmarshal(java.io.File f) throws JAXBException;

  /**
   * Unmarshal XML data from the specified InputStream and return the
   * resulting content tree.  Validation event location information may
   * be incomplete when using this form of the unmarshal API.
   *
   * <p>
   * Implements <a href="#unmarshalGlobal">Unmarshal Global Root Element</a>.
   *
   * @param is the InputStream to unmarshal XML data from
   * @return the newly created root object of the java content tree
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If the InputStream parameter is null
   */
  public Object unmarshal(java.io.InputStream is) throws JAXBException;

  /**
   * Unmarshal XML data from the specified Reader and return the
   * resulting content tree.  Validation event location information may
   * be incomplete when using this form of the unmarshal API,
   * because a Reader does not provide the system ID.
   *
   * <p>
   * Implements <a href="#unmarshalGlobal">Unmarshal Global Root Element</a>.
   *
   * @param reader the Reader to unmarshal XML data from
   * @return the newly created root object of the java content tree
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If the InputStream parameter is null
   * @since JAXB2.0
   */
  public Object unmarshal(Reader reader) throws JAXBException;

  /**
   * Unmarshal XML data from the specified URL and return the resulting
   * content tree.
   *
   * <p>
   * Implements <a href="#unmarshalGlobal">Unmarshal Global Root Element</a>.
   *
   * @param url the url to unmarshal XML data from
   * @return the newly created root object of the java content tree
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If the URL parameter is null
   */
  public Object unmarshal(java.net.URL url) throws JAXBException;

  /**
   * Unmarshal XML data from the specified SAX InputSource and return the
   * resulting content tree.
   *
   * <p>
   * Implements <a href="#unmarshalGlobal">Unmarshal Global Root Element</a>.
   *
   * @param source the input source to unmarshal XML data from
   * @return the newly created root object of the java content tree
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If the InputSource parameter is null
   */
  public Object unmarshal(org.xml.sax.InputSource source) throws JAXBException;

  /**
   * Unmarshal global XML data from the specified DOM tree and return the resulting
   * content tree.
   *
   * <p>
   * Implements <a href="#unmarshalGlobal">Unmarshal Global Root Element</a>.
   *
   * @param node the document/element to unmarshal XML data from. The caller must support at least
   * Document and Element.
   * @return the newly created root object of the java content tree
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If the Node parameter is null
   * @see #unmarshal(org.w3c.dom.Node, Class)
   */
  public Object unmarshal(org.w3c.dom.Node node) throws JAXBException;

  /**
   * Unmarshal XML data by JAXB mapped <tt>declaredType</tt>
   * and return the resulting content tree.
   *
   * <p>
   * Implements <a href="#unmarshalByDeclaredType">Unmarshal by Declared Type</a>
   *
   * @param node the document/element to unmarshal XML data from. The caller must support at least
   * Document and Element.
   * @param declaredType appropriate JAXB mapped class to hold <tt>node</tt>'s XML data.
   * @return <a href="#unmarshalDeclaredTypeReturn">JAXB Element</a> representation of <tt>node</tt>
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If any parameter is null
   * @since JAXB2.0
   */
  public <T> JAXBElement<T> unmarshal(org.w3c.dom.Node node, Class<T> declaredType)
      throws JAXBException;

  /**
   * Unmarshal XML data from the specified XML Source and return the
   * resulting content tree.
   *
   * <p>
   * Implements <a href="#unmarshalGlobal">Unmarshal Global Root Element</a>.
   *
   * <p>
   * <a name="saxParserPlugable"></a>
   * <b>SAX 2.0 Parser Pluggability</b>
   * <p>
   * A client application can choose not to use the default parser mechanism
   * supplied with their JAXB provider.  Any SAX 2.0 compliant parser can be
   * substituted for the JAXB provider's default mechanism.  To do so, the
   * client application must properly configure a <tt>SAXSource</tt> containing
   * an <tt>XMLReader</tt> implemented by the SAX 2.0 parser provider.  If the
   * <tt>XMLReader</tt> has an <tt>org.xml.sax.ErrorHandler</tt> registered
   * on it, it will be replaced by the JAXB Provider so that validation errors
   * can be reported via the <tt>ValidationEventHandler</tt> mechanism of
   * JAXB.  If the <tt>SAXSource</tt> does not contain an <tt>XMLReader</tt>,
   * then the JAXB provider's default parser mechanism will be used.
   * <p>
   * This parser replacement mechanism can also be used to replace the JAXB
   * provider's unmarshal-time validation engine.  The client application
   * must properly configure their SAX 2.0 compliant parser to perform
   * validation (as shown in the example above).  Any <tt>SAXParserExceptions
   * </tt> encountered by the parser during the unmarshal operation will be
   * processed by the JAXB provider and converted into JAXB
   * <tt>ValidationEvent</tt> objects which will be reported back to the
   * client via the <tt>ValidationEventHandler</tt> registered with the
   * <tt>Unmarshaller</tt>.  <i>Note:</i> specifying a substitute validating
   * SAX 2.0 parser for unmarshalling does not necessarily replace the
   * validation engine used by the JAXB provider for performing on-demand
   * validation.
   * <p>
   * The only way for a client application to specify an alternate parser
   * mechanism to be used during unmarshal is via the
   * <tt>unmarshal(SAXSource)</tt> API.  All other forms of the unmarshal
   * method (File, URL, Node, etc) will use the JAXB provider's default
   * parser and validator mechanisms.
   *
   * @param source the XML Source to unmarshal XML data from (providers are only required to support
   * SAXSource, DOMSource, and StreamSource)
   * @return the newly created root object of the java content tree
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If the Source parameter is null
   * @see #unmarshal(javax.xml.transform.Source, Class)
   */
  public Object unmarshal(javax.xml.transform.Source source)
      throws JAXBException;


  /**
   * Unmarshal XML data from the specified XML Source by <tt>declaredType</tt> and return the
   * resulting content tree.
   *
   * <p>
   * Implements <a href="#unmarshalByDeclaredType">Unmarshal by Declared Type</a>
   *
   * <p>
   * See <a href="#saxParserPlugable">SAX 2.0 Parser Pluggability</a>
   *
   * @param source the XML Source to unmarshal XML data from (providers are only required to support
   * SAXSource, DOMSource, and StreamSource)
   * @param declaredType appropriate JAXB mapped class to hold <tt>source</tt>'s xml root element
   * @return Java content rooted by <a href="#unmarshalDeclaredTypeReturn">JAXB Element</a>
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If any parameter is null
   * @since JAXB2.0
   */
  public <T> JAXBElement<T> unmarshal(javax.xml.transform.Source source, Class<T> declaredType)
      throws JAXBException;

  /**
   * Unmarshal XML data from the specified pull parser and return the
   * resulting content tree.
   *
   * <p>
   * Implements <a href="#unmarshalGlobal">Unmarshal Global Root Element</a>.
   *
   * <p>
   * This method assumes that the parser is on a START_DOCUMENT or
   * START_ELEMENT event.  Unmarshalling will be done from this
   * start event to the corresponding end event.  If this method
   * returns successfully, the <tt>reader</tt> will be pointing at
   * the token right after the end event.
   *
   * @param reader The parser to be read.
   * @return the newly created root object of the java content tree.
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If the <tt>reader</tt> parameter is null
   * @throws IllegalStateException If <tt>reader</tt> is not pointing to a START_DOCUMENT or
   * START_ELEMENT  event.
   * @see #unmarshal(javax.xml.stream.XMLStreamReader, Class)
   * @since JAXB2.0
   */
  public Object unmarshal(javax.xml.stream.XMLStreamReader reader)
      throws JAXBException;

  /**
   * Unmarshal root element to JAXB mapped <tt>declaredType</tt>
   * and return the resulting content tree.
   *
   * <p>
   * This method implements <a href="#unmarshalByDeclaredType">unmarshal by declaredType</a>.
   * <p>
   * This method assumes that the parser is on a START_DOCUMENT or
   * START_ELEMENT event. Unmarshalling will be done from this
   * start event to the corresponding end event.  If this method
   * returns successfully, the <tt>reader</tt> will be pointing at
   * the token right after the end event.
   *
   * @param reader The parser to be read.
   * @param declaredType appropriate JAXB mapped class to hold <tt>reader</tt>'s START_ELEMENT XML
   * data.
   * @return content tree rooted by <a href="#unmarshalDeclaredTypeReturn">JAXB Element
   * representation</a>
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If any parameter is null
   * @since JAXB2.0
   */
  public <T> JAXBElement<T> unmarshal(javax.xml.stream.XMLStreamReader reader,
      Class<T> declaredType) throws JAXBException;

  /**
   * Unmarshal XML data from the specified pull parser and return the
   * resulting content tree.
   *
   * <p>
   * This method is an <a href="#unmarshalGlobal">Unmarshal Global Root method</a>.
   *
   * <p>
   * This method assumes that the parser is on a START_DOCUMENT or
   * START_ELEMENT event.  Unmarshalling will be done from this
   * start event to the corresponding end event.  If this method
   * returns successfully, the <tt>reader</tt> will be pointing at
   * the token right after the end event.
   *
   * @param reader The parser to be read.
   * @return the newly created root object of the java content tree.
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If the <tt>reader</tt> parameter is null
   * @throws IllegalStateException If <tt>reader</tt> is not pointing to a START_DOCUMENT or
   * START_ELEMENT event.
   * @see #unmarshal(javax.xml.stream.XMLEventReader, Class)
   * @since JAXB2.0
   */
  public Object unmarshal(javax.xml.stream.XMLEventReader reader)
      throws JAXBException;

  /**
   * Unmarshal root element to JAXB mapped <tt>declaredType</tt>
   * and return the resulting content tree.
   *
   * <p>
   * This method implements <a href="#unmarshalByDeclaredType">unmarshal by declaredType</a>.
   *
   * <p>
   * This method assumes that the parser is on a START_DOCUMENT or
   * START_ELEMENT event. Unmarshalling will be done from this
   * start event to the corresponding end event.  If this method
   * returns successfully, the <tt>reader</tt> will be pointing at
   * the token right after the end event.
   *
   * @param reader The parser to be read.
   * @param declaredType appropriate JAXB mapped class to hold <tt>reader</tt>'s START_ELEMENT XML
   * data.
   * @return content tree rooted by <a href="#unmarshalDeclaredTypeReturn">JAXB Element
   * representation</a>
   * @throws JAXBException If any unexpected errors occur while unmarshalling
   * @throws UnmarshalException If the {@link ValidationEventHandler ValidationEventHandler} returns
   * false from its <tt>handleEvent</tt> method or the <tt>Unmarshaller</tt> is unable to perform
   * the XML to Java binding.  See <a href="#unmarshalEx">Unmarshalling XML Data</a>
   * @throws IllegalArgumentException If any parameter is null
   * @since JAXB2.0
   */
  public <T> JAXBElement<T> unmarshal(javax.xml.stream.XMLEventReader reader, Class<T> declaredType)
      throws JAXBException;

  /**
   * Get an unmarshaller handler object that can be used as a component in
   * an XML pipeline.
   *
   * <p>
   * The JAXB Provider can return the same handler object for multiple
   * invocations of this method. In other words, this method does not
   * necessarily create a new instance of <tt>UnmarshallerHandler</tt>. If the
   * application needs to use more than one <tt>UnmarshallerHandler</tt>, it
   * should create more than one <tt>Unmarshaller</tt>.
   *
   * @return the unmarshaller handler object
   * @see UnmarshallerHandler
   */
  public UnmarshallerHandler getUnmarshallerHandler();

  /**
   * Specifies whether or not the default validation mechanism of the
   * <tt>Unmarshaller</tt> should validate during unmarshal operations.
   * By default, the <tt>Unmarshaller</tt> does not validate.
   * <p>
   * This method may only be invoked before or after calling one of the
   * unmarshal methods.
   * <p>
   * This method only controls the JAXB Provider's default unmarshal-time
   * validation mechanism - it has no impact on clients that specify their
   * own validating SAX 2.0 compliant parser.  Clients that specify their
   * own unmarshal-time validation mechanism may wish to turn off the JAXB
   * Provider's default validation mechanism via this API to avoid "double
   * validation".
   * <p>
   * This method is deprecated as of JAXB 2.0 - please use the new
   * {@link #setSchema(javax.xml.validation.Schema)} API.
   *
   * @param validating true if the Unmarshaller should validate during unmarshal, false otherwise
   * @throws JAXBException if an error occurred while enabling or disabling validation at unmarshal
   * time
   * @throws UnsupportedOperationException could be thrown if this method is invoked on an
   * Unmarshaller created from a JAXBContext referencing JAXB 2.0 mapped classes
   * @deprecated since JAXB2.0, please see {@link #setSchema(javax.xml.validation.Schema)}
   */
  public void setValidating(boolean validating)
      throws JAXBException;

  /**
   * Indicates whether or not the <tt>Unmarshaller</tt> is configured to
   * validate during unmarshal operations.
   * <p>
   * This API returns the state of the JAXB Provider's default unmarshal-time
   * validation mechanism.
   * <p>
   * This method is deprecated as of JAXB 2.0 - please use the new
   * {@link #getSchema()} API.
   *
   * @return true if the Unmarshaller is configured to validate during unmarshal operations, false
   * otherwise
   * @throws JAXBException if an error occurs while retrieving the validating flag
   * @throws UnsupportedOperationException could be thrown if this method is invoked on an
   * Unmarshaller created from a JAXBContext referencing JAXB 2.0 mapped classes
   * @deprecated since JAXB2.0, please see {@link #getSchema()}
   */
  public boolean isValidating()
      throws JAXBException;

  /**
   * Allow an application to register a <tt>ValidationEventHandler</tt>.
   * <p>
   * The <tt>ValidationEventHandler</tt> will be called by the JAXB Provider
   * if any validation errors are encountered during calls to any of the
   * unmarshal methods.  If the client application does not register a
   * <tt>ValidationEventHandler</tt> before invoking the unmarshal methods,
   * then <tt>ValidationEvents</tt> will be handled by the default event
   * handler which will terminate the unmarshal operation after the first
   * error or fatal error is encountered.
   * <p>
   * Calling this method with a null parameter will cause the Unmarshaller
   * to revert back to the default event handler.
   *
   * @param handler the validation event handler
   * @throws JAXBException if an error was encountered while setting the event handler
   */
  public void setEventHandler(ValidationEventHandler handler)
      throws JAXBException;

  /**
   * Return the current event handler or the default event handler if one
   * hasn't been set.
   *
   * @return the current ValidationEventHandler or the default event handler if it hasn't been set
   * @throws JAXBException if an error was encountered while getting the current event handler
   */
  public ValidationEventHandler getEventHandler()
      throws JAXBException;

  /**
   * Set the particular property in the underlying implementation of
   * <tt>Unmarshaller</tt>.  This method can only be used to set one of
   * the standard JAXB defined properties above or a provider specific
   * property.  Attempting to set an undefined property will result in
   * a PropertyException being thrown.  See <a href="#supportedProps">
   * Supported Properties</a>.
   *
   * @param name the name of the property to be set. This value can either be specified using one of
   * the constant fields or a user supplied string.
   * @param value the value of the property to be set
   * @throws PropertyException when there is an error processing the given property or value
   * @throws IllegalArgumentException If the name parameter is null
   */
  public void setProperty(String name, Object value)
      throws PropertyException;

  /**
   * Get the particular property in the underlying implementation of
   * <tt>Unmarshaller</tt>.  This method can only be used to get one of
   * the standard JAXB defined properties above or a provider specific
   * property.  Attempting to get an undefined property will result in
   * a PropertyException being thrown.  See <a href="#supportedProps">
   * Supported Properties</a>.
   *
   * @param name the name of the property to retrieve
   * @return the value of the requested property
   * @throws PropertyException when there is an error retrieving the given property or value
   * property name
   * @throws IllegalArgumentException If the name parameter is null
   */
  public Object getProperty(String name) throws PropertyException;

  /**
   * Specify the JAXP 1.3 {@link javax.xml.validation.Schema Schema}
   * object that should be used to validate subsequent unmarshal operations
   * against.  Passing null into this method will disable validation.
   * <p>
   * This method replaces the deprecated {@link #setValidating(boolean) setValidating(boolean)}
   * API.
   *
   * <p>
   * Initially this property is set to <tt>null</tt>.
   *
   * @param schema Schema object to validate unmarshal operations against or null to disable
   * validation
   * @throws UnsupportedOperationException could be thrown if this method is invoked on an
   * Unmarshaller created from a JAXBContext referencing JAXB 1.0 mapped classes
   * @since JAXB2.0
   */
  public void setSchema(javax.xml.validation.Schema schema);

  /**
   * Get the JAXP 1.3 {@link javax.xml.validation.Schema Schema} object
   * being used to perform unmarshal-time validation.  If there is no
   * Schema set on the unmarshaller, then this method will return null
   * indicating that unmarshal-time validation will not be performed.
   * <p>
   * This method provides replacement functionality for the deprecated
   * {@link #isValidating()} API as well as access to the Schema object.
   * To determine if the Unmarshaller has validation enabled, simply
   * test the return type for null:
   * <p>
   * <code>
   * boolean isValidating = u.getSchema()!=null;
   * </code>
   *
   * @return the Schema object being used to perform unmarshal-time validation or null if not
   * present
   * @throws UnsupportedOperationException could be thrown if this method is invoked on an
   * Unmarshaller created from a JAXBContext referencing JAXB 1.0 mapped classes
   * @since JAXB2.0
   */
  public javax.xml.validation.Schema getSchema();

  /**
   * Associates a configured instance of {@link XmlAdapter} with this unmarshaller.
   *
   * <p>
   * This is a convenience method that invokes <code>setAdapter(adapter.getClass(),adapter);</code>.
   *
   * @throws IllegalArgumentException if the adapter parameter is null.
   * @throws UnsupportedOperationException if invoked agains a JAXB 1.0 implementation.
   * @see #setAdapter(Class, XmlAdapter)
   * @since JAXB2.0
   */
  public void setAdapter(XmlAdapter adapter);

  /**
   * Associates a configured instance of {@link XmlAdapter} with this unmarshaller.
   *
   * <p>
   * Every unmarshaller internally maintains a
   * {@link java.util.Map}&lt;{@link Class},{@link XmlAdapter}>,
   * which it uses for unmarshalling classes whose fields/methods are annotated
   * with {@link javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter}.
   *
   * <p>
   * This method allows applications to use a configured instance of {@link XmlAdapter}.
   * When an instance of an adapter is not given, an unmarshaller will create
   * one by invoking its default constructor.
   *
   * @param type The type of the adapter. The specified instance will be used when {@link
   * javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter#value()} refers to this type.
   * @param adapter The instance of the adapter to be used. If null, it will un-register the current
   * adapter set for this type.
   * @throws IllegalArgumentException if the type parameter is null.
   * @throws UnsupportedOperationException if invoked agains a JAXB 1.0 implementation.
   * @since JAXB2.0
   */
  public <A extends XmlAdapter> void setAdapter(Class<A> type, A adapter);

  /**
   * Gets the adapter associated with the specified type.
   *
   * This is the reverse operation of the {@link #setAdapter} method.
   *
   * @throws IllegalArgumentException if the type parameter is null.
   * @throws UnsupportedOperationException if invoked agains a JAXB 1.0 implementation.
   * @since JAXB2.0
   */
  public <A extends XmlAdapter> A getAdapter(Class<A> type);

  /**
   * <p>Associate a context that resolves cid's, content-id URIs, to
   * binary data passed as attachments.</p>
   * <p/>
   * <p>Unmarshal time validation, enabled via {@link #setSchema(Schema)},
   * must be supported even when unmarshaller is performing XOP processing.
   * </p>
   *
   * @throws IllegalStateException if attempt to concurrently call this method during a unmarshal
   * operation.
   */
  void setAttachmentUnmarshaller(AttachmentUnmarshaller au);

  AttachmentUnmarshaller getAttachmentUnmarshaller();

  /**
   * <p/>
   * Register an instance of an implementation of this class with {@link Unmarshaller} to externally
   * listen for unmarshal events.
   * <p/>
   * <p/>
   * This class enables pre and post processing of an instance of a JAXB mapped class as XML data is
   * unmarshalled into it. The event callbacks are called when unmarshalling XML content into a
   * JAXBElement instance or a JAXB mapped class that represents a complex type definition. The
   * event callbacks are not called when unmarshalling to an instance of a Java datatype that
   * represents a simple type definition.
   * <p/>
   * <p/>
   * External listener is one of two different mechanisms for defining unmarshal event callbacks.
   * See <a href="Unmarshaller.html#unmarshalEventCallback">Unmarshal Event Callbacks</a> for an
   * overview.
   * <p/>
   * (@link #setListener(Listener)} (@link #getListener()}
   *
   * @since JAXB2.0
   */
  public static abstract class Listener {

    /**
     * <p/>
     * Callback method invoked before unmarshalling into <tt>target</tt>.
     * <p/>
     * <p/>
     * This method is invoked immediately after <tt>target</tt> was created and
     * before the unmarshalling of this object begins. Note that
     * if the class of <tt>target</tt> defines its own <tt>beforeUnmarshal</tt> method,
     * the class specific callback method is invoked before this method is invoked.
     *
     * @param target non-null instance of JAXB mapped class prior to unmarshalling into it.
     * @param parent instance of JAXB mapped class that will eventually reference <tt>target</tt>.
     * <tt>null</tt> when <tt>target</tt> is root element.
     */
    public void beforeUnmarshal(Object target, Object parent) {
    }

    /**
     * <p/>
     * Callback method invoked after unmarshalling XML data into <tt>target</tt>.
     * <p/>
     * <p/>
     * This method is invoked after all the properties (except IDREF) are unmarshalled into
     * <tt>target</tt>, but before <tt>target</tt> is set into its <tt>parent</tt> object. Note that
     * if the class of <tt>target</tt> defines its own <tt>afterUnmarshal</tt> method, the class
     * specific callback method is invoked before this method is invoked.
     *
     * @param target non-null instance of JAXB mapped class prior to unmarshalling into it.
     * @param parent instance of JAXB mapped class that will reference <tt>target</tt>.
     * <tt>null</tt> when <tt>target</tt> is root element.
     */
    public void afterUnmarshal(Object target, Object parent) {
    }
  }

  /**
   * <p> Register unmarshal event callback {@link Listener} with this {@link Unmarshaller}.
   *
   * <p> There is only one Listener per Unmarshaller. Setting a Listener replaces the previous set
   * Listener. One can unregister current Listener by setting listener to <tt>null</tt>.
   *
   * @param listener provides unmarshal event callbacks for this {@link Unmarshaller}
   * @since JAXB2.0
   */
  public void setListener(Listener listener);

  /**
   * <p>Return {@link Listener} registered with this {@link Unmarshaller}.
   *
   * @return registered {@link Listener} or <code>null</code> if no Listener is registered with this
   * Unmarshaller.
   * @since JAXB2.0
   */
  public Listener getListener();
}
